This invention relates to the field of water beds and more particularly to the type of padded side rails which have been developed for installation on the frames holding water beds to provide a more pleasing appearance, to secure the water bed in position, and to provide a more comfortable surface for persons entering or leaving the water bed.
A standard water bed in essence consists of a rectangular frame, most often built of vertical wood sections having a uniform thickness and having the appearance of wide planks. The primary purpose of the water bed frame is to structurally retain and hold an inner liner which is filled with water. Unlike conventional beds which have relatively soft mattress sides rising above their frames, a water bed side frame must extend to the top of the water bed mattress to provide sufficient retention strength to hold the liner in place. As a result, a person climbing into or out of a water bed contacts the side rail or the side frame which is a particularly hard and unyielding material having relatively sharp corners.
As a result, a specific sub-technology has grown up in water beds for the construction of various decorative and padded end rails or rail caps which serve the twin purposes of protecting the user against the hard edges of the water bed frame by providing a soft and yielding surface, and, at the same time, providing a more pleasing appearance to the water bed.
Typical of such retainer caps or rails caps is that shown in U.S. Pat. No. 4,109,887 of Wakeland which shows a plurality of methods for retaining a water bed cap upon a rail. Similarly, U.S. Pat. No. 4,089,497, Miller, shows an alternate method of retaining a padded cap upon a water bed rail.
U.S. Pat. No. 4,103,375, Santo, shows a particular type of water bed frame. U.S. Pat. No. 3,973,282, May, includes in its description and drawings a good representation of the most common water bed frame technique now in use. U.S. Pat. No. 4,109,887, Wakeland, also includes a good description of the state of the art in water bed frames and rails. U.S. Pat. No. 3,840,921, LaBianco, shows one alternate water bed frame member.